We're dividing 343915 by 99 
We want to figure out the number of times 343915 can be divided by 99.

Going ahead to step 1:
If we divide 3 by 99, we get 0 and a remainder of 3.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 3, we end up with 3.
Take the next digit (4) from the dividend and append it to 3, then repeat: 34 / 99

Step 2:
When dividing 34 by 99, we get 0 with a remainder of 34.
Write down 0 as next digit of the result. 
Result so far: 0.0
Subtract 0 from 34 to get 34.
Include the next digit (3) from the dividend after 34, then repeat: 343 / 99

Let's proceed to step 3:
The number 99 fits into 343 3 times, leaving a remainder of 46.
Put 3 as the next digit of the answer. 
Result so far: 3.0
If we take 297 away from 343, we end up with 46.
Append the next digit (9) from the dividend to 46 and continue with: 469 / 99

Step 4:
If we divide 469 by 99, we get 4 and a remainder of 73.
Write down 4 as next digit of the result. 
Result so far: 34.0
If we take 396 away from 469, we end up with 73.
Include the next digit (1) from the dividend after 73, then repeat: 731 / 99

Moving on to step 5:
99 goes into 731 7 times with a remainder of 38.
Put 7 as the next digit of the answer. 
Result so far: 347.0
Subtract 693 from 731 to get 38.
Bring next digit (5) of the dividend behind the 38 and repeat the process: 385 / 99

Step 6:
If we divide 385 by 99, we get 3 and a remainder of 88.
Write down 3 as next digit of the result. 
Result so far: 3473.0
If we take 297 away from 385, we end up with 88.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

On to step 7:
99 goes into 880 8 times with a remainder of 88.
Put 8 as the next digit of the answer. 
Result so far: 3473.8
Subtract 792 from 880 to get 88.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

Step 8:
When dividing 880 by 99, we get 8 with a remainder of 88.
The number 8 becomes the next digit in our result. 
Result so far: 3473.88
The remainder is 88 after subtracting 792 from 880.
Since there are no more digits in the dividend, we add a zero to the remainder making it 880, and continue the process.

After the division, we end up with 3473.88 and a remainder of 0.088.